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/* ieee754-sf.S single-precision floating point support for ARM

   Copyright (C) 2003, 2004, 2005  Free Software Foundation, Inc.
   Contributed by Nicolas Pitre (nico@cam.org)

   This file is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the
   Free Software Foundation; either version 2, or (at your option) any
   later version.

   In addition to the permissions in the GNU General Public License, the
   Free Software Foundation gives you unlimited permission to link the
   compiled version of this file into combinations with other programs,
   and to distribute those combinations without any restriction coming
   from the use of this file.  (The General Public License restrictions
   do apply in other respects; for example, they cover modification of
   the file, and distribution when not linked into a combine
   executable.)

   This file is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.  If not, write to
   the Free Software Foundation, 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.  */

/*
 * Notes:
 *
 * The goal of this code is to be as fast as possible.  This is
 * not meant to be easy to understand for the casual reader.
 *
 * Only the default rounding mode is intended for best performances.
 * Exceptions aren't supported yet, but that can be added quite easily
 * if necessary without impacting performances.
 */

#ifdef L_negsf2
        
ARM_FUNC_START negsf2
ARM_FUNC_ALIAS aeabi_fneg negsf2

        eor     r0, r0, #0x80000000     @ flip sign bit
        RET

        FUNC_END aeabi_fneg
        FUNC_END negsf2

#endif

#ifdef L_addsubsf3

ARM_FUNC_START aeabi_frsub

        eor     r0, r0, #0x80000000     @ flip sign bit of first arg
        b       1f

ARM_FUNC_START subsf3
ARM_FUNC_ALIAS aeabi_fsub subsf3

        eor     r1, r1, #0x80000000     @ flip sign bit of second arg
#if defined(__INTERWORKING_STUBS__)
        b       1f                      @ Skip Thumb-code prologue
#endif

ARM_FUNC_START addsf3
ARM_FUNC_ALIAS aeabi_fadd addsf3

1:      @ Look for zeroes, equal values, INF, or NAN.
        movs    r2, r0, lsl #1
        movnes  r3, r1, lsl #1
        teqne   r2, r3
        mvnnes  ip, r2, asr #24
        mvnnes  ip, r3, asr #24
        beq     LSYM(Lad_s)

        @ Compute exponent difference.  Make largest exponent in r2,
        @ corresponding arg in r0, and positive exponent difference in r3.
        mov     r2, r2, lsr #24
        rsbs    r3, r2, r3, lsr #24
        addgt   r2, r2, r3
        eorgt   r1, r0, r1
        eorgt   r0, r1, r0
        eorgt   r1, r0, r1
        rsblt   r3, r3, #0

        @ If exponent difference is too large, return largest argument
        @ already in r0.  We need up to 25 bit to handle proper rounding
        @ of 0x1p25 - 1.1.
        cmp     r3, #25
        RETc(hi)

        @ Convert mantissa to signed integer.
        tst     r0, #0x80000000
        orr     r0, r0, #0x00800000
        bic     r0, r0, #0xff000000
        rsbne   r0, r0, #0
        tst     r1, #0x80000000
        orr     r1, r1, #0x00800000
        bic     r1, r1, #0xff000000
        rsbne   r1, r1, #0

        @ If exponent == difference, one or both args were denormalized.
        @ Since this is not common case, rescale them off line.
        teq     r2, r3
        beq     LSYM(Lad_d)
LSYM(Lad_x):

        @ Compensate for the exponent overlapping the mantissa MSB added later
        sub     r2, r2, #1

        @ Shift and add second arg to first arg in r0.
        @ Keep leftover bits into r1.
        adds    r0, r0, r1, asr r3
        rsb     r3, r3, #32
        mov     r1, r1, lsl r3

        @ Keep absolute value in r0-r1, sign in r3 (the n bit was set above)
        and     r3, r0, #0x80000000
        bpl     LSYM(Lad_p)
        rsbs    r1, r1, #0
        rsc     r0, r0, #0

        @ Determine how to normalize the result.
LSYM(Lad_p):
        cmp     r0, #0x00800000
        bcc     LSYM(Lad_a)
        cmp     r0, #0x01000000
        bcc     LSYM(Lad_e)

        @ Result needs to be shifted right.
        movs    r0, r0, lsr #1
        mov     r1, r1, rrx
        add     r2, r2, #1

        @ Make sure we did not bust our exponent.
        cmp     r2, #254
        bhs     LSYM(Lad_o)

        @ Our result is now properly aligned into r0, remaining bits in r1.
        @ Pack final result together.
        @ Round with MSB of r1. If halfway between two numbers, round towards
        @ LSB of r0 = 0. 
LSYM(Lad_e):
        cmp     r1, #0x80000000
        adc     r0, r0, r2, lsl #23
        biceq   r0, r0, #1
        orr     r0, r0, r3
        RET

        @ Result must be shifted left and exponent adjusted.
LSYM(Lad_a):
        movs    r1, r1, lsl #1
        adc     r0, r0, r0
        tst     r0, #0x00800000
        sub     r2, r2, #1
        bne     LSYM(Lad_e)
        
        @ No rounding necessary since r1 will always be 0 at this point.
LSYM(Lad_l):

#if __ARM_ARCH__ < 5

        movs    ip, r0, lsr #12
        moveq   r0, r0, lsl #12
        subeq   r2, r2, #12
        tst     r0, #0x00ff0000
        moveq   r0, r0, lsl #8
        subeq   r2, r2, #8
        tst     r0, #0x00f00000
        moveq   r0, r0, lsl #4
        subeq   r2, r2, #4
        tst     r0, #0x00c00000
        moveq   r0, r0, lsl #2
        subeq   r2, r2, #2
        cmp     r0, #0x00800000
        movcc   r0, r0, lsl #1
        sbcs    r2, r2, #0

#else

        clz     ip, r0
        sub     ip, ip, #8
        subs    r2, r2, ip
        mov     r0, r0, lsl ip

#endif

        @ Final result with sign
        @ If exponent negative, denormalize result.
        addge   r0, r0, r2, lsl #23
        rsblt   r2, r2, #0
        orrge   r0, r0, r3
        orrlt   r0, r3, r0, lsr r2
        RET

        @ Fixup and adjust bit position for denormalized arguments.
        @ Note that r2 must not remain equal to 0.
LSYM(Lad_d):
        teq     r2, #0
        eor     r1, r1, #0x00800000
        eoreq   r0, r0, #0x00800000
        addeq   r2, r2, #1
        subne   r3, r3, #1
        b       LSYM(Lad_x)

LSYM(Lad_s):
        mov     r3, r1, lsl #1

        mvns    ip, r2, asr #24
        mvnnes  ip, r3, asr #24
        beq     LSYM(Lad_i)

        teq     r2, r3
        beq     1f

        @ Result is x + 0.0 = x or 0.0 + y = y.
        teq     r2, #0
        moveq   r0, r1
        RET

1:      teq     r0, r1

        @ Result is x - x = 0.
        movne   r0, #0
        RETc(ne)

        @ Result is x + x = 2x.
        tst     r2, #0xff000000
        bne     2f
        movs    r0, r0, lsl #1
        orrcs   r0, r0, #0x80000000
        RET
2:      adds    r2, r2, #(2 << 24)
        addcc   r0, r0, #(1 << 23)
        RETc(cc)
        and     r3, r0, #0x80000000

        @ Overflow: return INF.
LSYM(Lad_o):
        orr     r0, r3, #0x7f000000
        orr     r0, r0, #0x00800000
        RET

        @ At least one of r0/r1 is INF/NAN.
        @   if r0 != INF/NAN: return r1 (which is INF/NAN)
        @   if r1 != INF/NAN: return r0 (which is INF/NAN)
        @   if r0 or r1 is NAN: return NAN
        @   if opposite sign: return NAN
        @   otherwise return r0 (which is INF or -INF)
LSYM(Lad_i):
        mvns    r2, r2, asr #24
        movne   r0, r1
        mvneqs  r3, r3, asr #24
        movne   r1, r0
        movs    r2, r0, lsl #9
        moveqs  r3, r1, lsl #9
        teqeq   r0, r1
        orrne   r0, r0, #0x00400000     @ quiet NAN
        RET

        FUNC_END aeabi_frsub
        FUNC_END aeabi_fadd
        FUNC_END addsf3
        FUNC_END aeabi_fsub
        FUNC_END subsf3

ARM_FUNC_START floatunsisf
ARM_FUNC_ALIAS aeabi_ui2f floatunsisf
                
        mov     r3, #0
        b       1f

ARM_FUNC_START floatsisf
ARM_FUNC_ALIAS aeabi_i2f floatsisf
        
        ands    r3, r0, #0x80000000
        rsbmi   r0, r0, #0

1:      movs    ip, r0
        RETc(eq)

        @ Add initial exponent to sign
        orr     r3, r3, #((127 + 23) << 23)

        .ifnc   ah, r0
        mov     ah, r0
        .endif
        mov     al, #0
        b       2f

        FUNC_END aeabi_i2f
        FUNC_END floatsisf
        FUNC_END aeabi_ui2f
        FUNC_END floatunsisf

ARM_FUNC_START floatundisf
ARM_FUNC_ALIAS aeabi_ul2f floatundisf

        orrs    r2, r0, r1
#if !defined (__VFP_FP__) && !defined(__SOFTFP__)
        mvfeqs  f0, #0.0
#endif
        RETc(eq)

        mov     r3, #0
        b       1f

ARM_FUNC_START floatdisf
ARM_FUNC_ALIAS aeabi_l2f floatdisf

        orrs    r2, r0, r1
#if !defined (__VFP_FP__) && !defined(__SOFTFP__)
        mvfeqs  f0, #0.0
#endif
        RETc(eq)

        ands    r3, ah, #0x80000000     @ sign bit in r3
        bpl     1f
        rsbs    al, al, #0
        rsc     ah, ah, #0
1:
#if !defined (__VFP_FP__) && !defined(__SOFTFP__)
        @ For hard FPA code we want to return via the tail below so that
        @ we can return the result in f0 as well as in r0 for backwards
        @ compatibility.
        str     lr, [sp, #-8]!
        adr     lr, LSYM(f0_ret)
#endif

        movs    ip, ah
        moveq   ip, al
        moveq   ah, al
        moveq   al, #0

        @ Add initial exponent to sign
        orr     r3, r3, #((127 + 23 + 32) << 23)
        subeq   r3, r3, #(32 << 23)
2:      sub     r3, r3, #(1 << 23)

#if __ARM_ARCH__ < 5

        mov     r2, #23
        cmp     ip, #(1 << 16)
        movhs   ip, ip, lsr #16
        subhs   r2, r2, #16
        cmp     ip, #(1 << 8)
        movhs   ip, ip, lsr #8
        subhs   r2, r2, #8
        cmp     ip, #(1 << 4)
        movhs   ip, ip, lsr #4
        subhs   r2, r2, #4
        cmp     ip, #(1 << 2)
        subhs   r2, r2, #2
        sublo   r2, r2, ip, lsr #1
        subs    r2, r2, ip, lsr #3

#else

        clz     r2, ip
        subs    r2, r2, #8

#endif

        sub     r3, r3, r2, lsl #23
        blt     3f

        add     r3, r3, ah, lsl r2
        mov     ip, al, lsl r2
        rsb     r2, r2, #32
        cmp     ip, #0x80000000
        adc     r0, r3, al, lsr r2
        biceq   r0, r0, #1
        RET

3:      add     r2, r2, #32
        mov     ip, ah, lsl r2
        rsb     r2, r2, #32
        orrs    al, al, ip, lsl #1
        adc     r0, r3, ah, lsr r2
        biceq   r0, r0, ip, lsr #31
        RET

#if !defined (__VFP_FP__) && !defined(__SOFTFP__)

LSYM(f0_ret):
        str     r0, [sp, #-4]!
        ldfs    f0, [sp], #4
        RETLDM

#endif

        FUNC_END floatdisf
        FUNC_END aeabi_l2f
        FUNC_END floatundisf
        FUNC_END aeabi_ul2f

#endif /* L_addsubsf3 */

#ifdef L_muldivsf3

ARM_FUNC_START mulsf3
ARM_FUNC_ALIAS aeabi_fmul mulsf3

        @ Mask out exponents, trap any zero/denormal/INF/NAN.
        mov     ip, #0xff
        ands    r2, ip, r0, lsr #23
        andnes  r3, ip, r1, lsr #23
        teqne   r2, ip
        teqne   r3, ip
        beq     LSYM(Lml_s)
LSYM(Lml_x):

        @ Add exponents together
        add     r2, r2, r3

        @ Determine final sign.
        eor     ip, r0, r1

        @ Convert mantissa to unsigned integer.
        @ If power of two, branch to a separate path.
        @ Make up for final alignment.
        movs    r0, r0, lsl #9
        movnes  r1, r1, lsl #9
        beq     LSYM(Lml_1)
        mov     r3, #0x08000000
        orr     r0, r3, r0, lsr #5
        orr     r1, r3, r1, lsr #5

#if __ARM_ARCH__ < 4

        @ Put sign bit in r3, which will be restored into r0 later.
        and     r3, ip, #0x80000000

        @ Well, no way to make it shorter without the umull instruction.
        stmfd   sp!, {r3, r4, r5}
        mov     r4, r0, lsr #16
        mov     r5, r1, lsr #16
        bic     r0, r0, r4, lsl #16
        bic     r1, r1, r5, lsl #16
        mul     ip, r4, r5
        mul     r3, r0, r1
        mul     r0, r5, r0
        mla     r0, r4, r1, r0
        adds    r3, r3, r0, lsl #16
        adc     r1, ip, r0, lsr #16
        ldmfd   sp!, {r0, r4, r5}

#else

        @ The actual multiplication.
        umull   r3, r1, r0, r1

        @ Put final sign in r0.
        and     r0, ip, #0x80000000

#endif

        @ Adjust result upon the MSB position.
        cmp     r1, #(1 << 23)
        movcc   r1, r1, lsl #1
        orrcc   r1, r1, r3, lsr #31
        movcc   r3, r3, lsl #1

        @ Add sign to result.
        orr     r0, r0, r1

        @ Apply exponent bias, check for under/overflow.
        sbc     r2, r2, #127
        cmp     r2, #(254 - 1)
        bhi     LSYM(Lml_u)

        @ Round the result, merge final exponent.
        cmp     r3, #0x80000000
        adc     r0, r0, r2, lsl #23
        biceq   r0, r0, #1
        RET

        @ Multiplication by 0x1p*: let''s shortcut a lot of code.
LSYM(Lml_1):
        teq     r0, #0
        and     ip, ip, #0x80000000
        moveq   r1, r1, lsl #9
        orr     r0, ip, r0, lsr #9
        orr     r0, r0, r1, lsr #9
        subs    r2, r2, #127
        rsbgts  r3, r2, #255
        orrgt   r0, r0, r2, lsl #23
        RETc(gt)

        @ Under/overflow: fix things up for the code below.
        orr     r0, r0, #0x00800000
        mov     r3, #0
        subs    r2, r2, #1

LSYM(Lml_u):
        @ Overflow?
        bgt     LSYM(Lml_o)

        @ Check if denormalized result is possible, otherwise return signed 0.
        cmn     r2, #(24 + 1)
        bicle   r0, r0, #0x7fffffff
        RETc(le)

        @ Shift value right, round, etc.
        rsb     r2, r2, #0
        movs    r1, r0, lsl #1
        mov     r1, r1, lsr r2
        rsb     r2, r2, #32
        mov     ip, r0, lsl r2
        movs    r0, r1, rrx
        adc     r0, r0, #0
        orrs    r3, r3, ip, lsl #1
        biceq   r0, r0, ip, lsr #31
        RET

        @ One or both arguments are denormalized.
        @ Scale them leftwards and preserve sign bit.
LSYM(Lml_d):
        teq     r2, #0
        and     ip, r0, #0x80000000
1:      moveq   r0, r0, lsl #1
        tsteq   r0, #0x00800000
        subeq   r2, r2, #1
        beq     1b
        orr     r0, r0, ip
        teq     r3, #0
        and     ip, r1, #0x80000000
2:      moveq   r1, r1, lsl #1
        tsteq   r1, #0x00800000
        subeq   r3, r3, #1
        beq     2b
        orr     r1, r1, ip
        b       LSYM(Lml_x)

LSYM(Lml_s):
        @ Isolate the INF and NAN cases away
        and     r3, ip, r1, lsr #23
        teq     r2, ip
        teqne   r3, ip
        beq     1f

        @ Here, one or more arguments are either denormalized or zero.
        bics    ip, r0, #0x80000000
        bicnes  ip, r1, #0x80000000
        bne     LSYM(Lml_d)

        @ Result is 0, but determine sign anyway.
LSYM(Lml_z):
        eor     r0, r0, r1
        bic     r0, r0, #0x7fffffff
        RET

1:      @ One or both args are INF or NAN.
        teq     r0, #0x0
        teqne   r0, #0x80000000
        moveq   r0, r1
        teqne   r1, #0x0
        teqne   r1, #0x80000000
        beq     LSYM(Lml_n)             @ 0 * INF or INF * 0 -> NAN
        teq     r2, ip
        bne     1f
        movs    r2, r0, lsl #9
        bne     LSYM(Lml_n)             @ NAN * <anything> -> NAN
1:      teq     r3, ip
        bne     LSYM(Lml_i)
        movs    r3, r1, lsl #9
        movne   r0, r1
        bne     LSYM(Lml_n)             @ <anything> * NAN -> NAN

        @ Result is INF, but we need to determine its sign.
LSYM(Lml_i):
        eor     r0, r0, r1

        @ Overflow: return INF (sign already in r0).
LSYM(Lml_o):
        and     r0, r0, #0x80000000
        orr     r0, r0, #0x7f000000
        orr     r0, r0, #0x00800000
        RET

        @ Return a quiet NAN.
LSYM(Lml_n):
        orr     r0, r0, #0x7f000000
        orr     r0, r0, #0x00c00000
        RET

        FUNC_END aeabi_fmul
        FUNC_END mulsf3

ARM_FUNC_START divsf3
ARM_FUNC_ALIAS aeabi_fdiv divsf3

        @ Mask out exponents, trap any zero/denormal/INF/NAN.
        mov     ip, #0xff
        ands    r2, ip, r0, lsr #23
        andnes  r3, ip, r1, lsr #23
        teqne   r2, ip
        teqne   r3, ip
        beq     LSYM(Ldv_s)
LSYM(Ldv_x):

        @ Substract divisor exponent from dividend''s
        sub     r2, r2, r3

        @ Preserve final sign into ip.
        eor     ip, r0, r1

        @ Convert mantissa to unsigned integer.
        @ Dividend -> r3, divisor -> r1.
        movs    r1, r1, lsl #9
        mov     r0, r0, lsl #9
        beq     LSYM(Ldv_1)
        mov     r3, #0x10000000
        orr     r1, r3, r1, lsr #4
        orr     r3, r3, r0, lsr #4

        @ Initialize r0 (result) with final sign bit.
        and     r0, ip, #0x80000000

        @ Ensure result will land to known bit position.
        @ Apply exponent bias accordingly.
        cmp     r3, r1
        movcc   r3, r3, lsl #1
        adc     r2, r2, #(127 - 2)

        @ The actual division loop.
        mov     ip, #0x00800000
1:      cmp     r3, r1
        subcs   r3, r3, r1
        orrcs   r0, r0, ip
        cmp     r3, r1, lsr #1
        subcs   r3, r3, r1, lsr #1
        orrcs   r0, r0, ip, lsr #1
        cmp     r3, r1, lsr #2
        subcs   r3, r3, r1, lsr #2
        orrcs   r0, r0, ip, lsr #2
        cmp     r3, r1, lsr #3
        subcs   r3, r3, r1, lsr #3
        orrcs   r0, r0, ip, lsr #3
        movs    r3, r3, lsl #4
        movnes  ip, ip, lsr #4
        bne     1b

        @ Check exponent for under/overflow.
        cmp     r2, #(254 - 1)
        bhi     LSYM(Lml_u)

        @ Round the result, merge final exponent.
        cmp     r3, r1
        adc     r0, r0, r2, lsl #23
        biceq   r0, r0, #1
        RET

        @ Division by 0x1p*: let''s shortcut a lot of code.
LSYM(Ldv_1):
        and     ip, ip, #0x80000000
        orr     r0, ip, r0, lsr #9
        adds    r2, r2, #127
        rsbgts  r3, r2, #255
        orrgt   r0, r0, r2, lsl #23
        RETc(gt)

        orr     r0, r0, #0x00800000
        mov     r3, #0
        subs    r2, r2, #1
        b       LSYM(Lml_u)

        @ One or both arguments are denormalized.
        @ Scale them leftwards and preserve sign bit.
LSYM(Ldv_d):
        teq     r2, #0
        and     ip, r0, #0x80000000
1:      moveq   r0, r0, lsl #1
        tsteq   r0, #0x00800000
        subeq   r2, r2, #1
        beq     1b
        orr     r0, r0, ip
        teq     r3, #0
        and     ip, r1, #0x80000000
2:      moveq   r1, r1, lsl #1
        tsteq   r1, #0x00800000
        subeq   r3, r3, #1
        beq     2b
        orr     r1, r1, ip
        b       LSYM(Ldv_x)

        @ One or both arguments are either INF, NAN, zero or denormalized.
LSYM(Ldv_s):
        and     r3, ip, r1, lsr #23
        teq     r2, ip
        bne     1f
        movs    r2, r0, lsl #9
        bne     LSYM(Lml_n)             @ NAN / <anything> -> NAN
        teq     r3, ip
        bne     LSYM(Lml_i)             @ INF / <anything> -> INF
        mov     r0, r1
        b       LSYM(Lml_n)             @ INF / (INF or NAN) -> NAN
1:      teq     r3, ip
        bne     2f
        movs    r3, r1, lsl #9
        beq     LSYM(Lml_z)             @ <anything> / INF -> 0
        mov     r0, r1
        b       LSYM(Lml_n)             @ <anything> / NAN -> NAN
2:      @ If both are nonzero, we need to normalize and resume above.
        bics    ip, r0, #0x80000000
        bicnes  ip, r1, #0x80000000
        bne     LSYM(Ldv_d)
        @ One or both arguments are zero.
        bics    r2, r0, #0x80000000
        bne     LSYM(Lml_i)             @ <non_zero> / 0 -> INF
        bics    r3, r1, #0x80000000
        bne     LSYM(Lml_z)             @ 0 / <non_zero> -> 0
        b       LSYM(Lml_n)             @ 0 / 0 -> NAN

        FUNC_END aeabi_fdiv
        FUNC_END divsf3

#endif /* L_muldivsf3 */

#ifdef L_cmpsf2

        @ The return value in r0 is
        @
        @   0  if the operands are equal
        @   1  if the first operand is greater than the second, or
        @      the operands are unordered and the operation is
        @      CMP, LT, LE, NE, or EQ.
        @   -1 if the first operand is less than the second, or
        @      the operands are unordered and the operation is GT
        @      or GE.
        @
        @ The Z flag will be set iff the operands are equal.
        @
        @ The following registers are clobbered by this function:
        @   ip, r0, r1, r2, r3

ARM_FUNC_START gtsf2
ARM_FUNC_ALIAS gesf2 gtsf2
        mov     ip, #-1
        b       1f

ARM_FUNC_START ltsf2
ARM_FUNC_ALIAS lesf2 ltsf2
        mov     ip, #1
        b       1f

ARM_FUNC_START cmpsf2
ARM_FUNC_ALIAS nesf2 cmpsf2
ARM_FUNC_ALIAS eqsf2 cmpsf2
        mov     ip, #1                  @ how should we specify unordered here?

1:      str     ip, [sp, #-4]

        @ Trap any INF/NAN first.
        mov     r2, r0, lsl #1
        mov     r3, r1, lsl #1
        mvns    ip, r2, asr #24
        mvnnes  ip, r3, asr #24
        beq     3f

        @ Compare values.
        @ Note that 0.0 is equal to -0.0.
2:      orrs    ip, r2, r3, lsr #1      @ test if both are 0, clear C flag
        teqne   r0, r1                  @ if not 0 compare sign
        subpls  r0, r2, r3              @ if same sign compare values, set r0

        @ Result:
        movhi   r0, r1, asr #31
        mvnlo   r0, r1, asr #31
        orrne   r0, r0, #1
        RET

        @ Look for a NAN. 
3:      mvns    ip, r2, asr #24
        bne     4f
        movs    ip, r0, lsl #9
        bne     5f                      @ r0 is NAN
4:      mvns    ip, r3, asr #24
        bne     2b
        movs    ip, r1, lsl #9
        beq     2b                      @ r1 is not NAN
5:      ldr     r0, [sp, #-4]           @ return unordered code.
        RET

        FUNC_END gesf2
        FUNC_END gtsf2
        FUNC_END lesf2
        FUNC_END ltsf2
        FUNC_END nesf2
        FUNC_END eqsf2
        FUNC_END cmpsf2

ARM_FUNC_START aeabi_cfrcmple

        mov     ip, r0
        mov     r0, r1
        mov     r1, ip
        b       6f

ARM_FUNC_START aeabi_cfcmpeq
ARM_FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq

        @ The status-returning routines are required to preserve all
        @ registers except ip, lr, and cpsr.
6:      stmfd   sp!, {r0, r1, r2, r3, lr}
        ARM_CALL cmpsf2
        @ Set the Z flag correctly, and the C flag unconditionally.
        cmp      r0, #0
        @ Clear the C flag if the return value was -1, indicating
        @ that the first operand was smaller than the second.
        cmnmi    r0, #0
        RETLDM  "r0, r1, r2, r3"

        FUNC_END aeabi_cfcmple
        FUNC_END aeabi_cfcmpeq
        FUNC_END aeabi_cfrcmple

ARM_FUNC_START  aeabi_fcmpeq

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfcmple
        moveq   r0, #1  @ Equal to.
        movne   r0, #0  @ Less than, greater than, or unordered.
        RETLDM

        FUNC_END aeabi_fcmpeq

ARM_FUNC_START  aeabi_fcmplt

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfcmple
        movcc   r0, #1  @ Less than.
        movcs   r0, #0  @ Equal to, greater than, or unordered.
        RETLDM

        FUNC_END aeabi_fcmplt

ARM_FUNC_START  aeabi_fcmple

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfcmple
        movls   r0, #1  @ Less than or equal to.
        movhi   r0, #0  @ Greater than or unordered.
        RETLDM

        FUNC_END aeabi_fcmple

ARM_FUNC_START  aeabi_fcmpge

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfrcmple
        movls   r0, #1  @ Operand 2 is less than or equal to operand 1.
        movhi   r0, #0  @ Operand 2 greater than operand 1, or unordered.
        RETLDM

        FUNC_END aeabi_fcmpge

ARM_FUNC_START  aeabi_fcmpgt

        str     lr, [sp, #-8]!
        ARM_CALL aeabi_cfrcmple
        movcc   r0, #1  @ Operand 2 is less than operand 1.
        movcs   r0, #0  @ Operand 2 is greater than or equal to operand 1,
                        @ or they are unordered.
        RETLDM

        FUNC_END aeabi_fcmpgt

#endif /* L_cmpsf2 */

#ifdef L_unordsf2

ARM_FUNC_START unordsf2
ARM_FUNC_ALIAS aeabi_fcmpun unordsf2

        mov     r2, r0, lsl #1
        mov     r3, r1, lsl #1
        mvns    ip, r2, asr #24
        bne     1f
        movs    ip, r0, lsl #9
        bne     3f                      @ r0 is NAN
1:      mvns    ip, r3, asr #24
        bne     2f
        movs    ip, r1, lsl #9
        bne     3f                      @ r1 is NAN
2:      mov     r0, #0                  @ arguments are ordered.
        RET
3:      mov     r0, #1                  @ arguments are unordered.
        RET

        FUNC_END aeabi_fcmpun
        FUNC_END unordsf2

#endif /* L_unordsf2 */

#ifdef L_fixsfsi

ARM_FUNC_START fixsfsi
ARM_FUNC_ALIAS aeabi_f2iz fixsfsi

        @ check exponent range.
        mov     r2, r0, lsl #1
        cmp     r2, #(127 << 24)
        bcc     1f                      @ value is too small
        mov     r3, #(127 + 31)
        subs    r2, r3, r2, lsr #24
        bls     2f                      @ value is too large

        @ scale value
        mov     r3, r0, lsl #8
        orr     r3, r3, #0x80000000
        tst     r0, #0x80000000         @ the sign bit
        mov     r0, r3, lsr r2
        rsbne   r0, r0, #0
        RET

1:      mov     r0, #0
        RET

2:      cmp     r2, #(127 + 31 - 0xff)
        bne     3f
        movs    r2, r0, lsl #9
        bne     4f                      @ r0 is NAN.
3:      ands    r0, r0, #0x80000000     @ the sign bit
        moveq   r0, #0x7fffffff         @ the maximum signed positive si
        RET

4:      mov     r0, #0                  @ What should we convert NAN to?
        RET

        FUNC_END aeabi_f2iz
        FUNC_END fixsfsi

#endif /* L_fixsfsi */

#ifdef L_fixunssfsi

ARM_FUNC_START fixunssfsi
ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi

        @ check exponent range.
        movs    r2, r0, lsl #1
        bcs     1f                      @ value is negative
        cmp     r2, #(127 << 24)
        bcc     1f                      @ value is too small
        mov     r3, #(127 + 31)
        subs    r2, r3, r2, lsr #24
        bmi     2f                      @ value is too large

        @ scale the value
        mov     r3, r0, lsl #8
        orr     r3, r3, #0x80000000
        mov     r0, r3, lsr r2
        RET

1:      mov     r0, #0
        RET

2:      cmp     r2, #(127 + 31 - 0xff)
        bne     3f
        movs    r2, r0, lsl #9
        bne     4f                      @ r0 is NAN.
3:      mov     r0, #0xffffffff         @ maximum unsigned si
        RET

4:      mov     r0, #0                  @ What should we convert NAN to?
        RET

        FUNC_END aeabi_f2uiz
        FUNC_END fixunssfsi

#endif /* L_fixunssfsi */

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